CONTINUOUS POSTOPERATIVE INFUSION OF A REGIONAL ANESTHETIC AFTER AN AMPUTATION OF THE LOWER-EXTREMITY - A RANDOMIZED CLINICAL-TRIAL

We performed a prospective, randomized clinical trial to determine whe ther continuous infusion of bupivacaine hydrochloride decreased the us e of narcotics for the relief of pain after an amputation, Twenty-one patients who were to have an amputation of the lower extremity because of ischemic necrosis secondary to peripheral vascular disease were di vided into two groups with use of a table of random numbers, Group A ( the treatment group) included nine patients who were to have a transti bial amputation, one patient who was to have a disarticulation at the knee, and one patient who was to have a transfemoral amputation, Group B (the control group) included seven patients, two patients, and one patient, respectively, After the amputation had been performed, a Teno n catheter was placed adjacent to the transected end of the sciatic or posterior tibial nerve, Postoperatively, the patients received contin uous infusion of either bupivacaine (Group A) or normal saline solutio n (Group B) for seventy-two hours, Intravenous administration of morph ine with use of a patient-controlled pump also was permitted during th is period, The amount of morphine that was used was recorded meticulou sly, The patients in Group A used less morphine during the first and s econd days after the operation than did those in Group B, There was no difference between the groups with regard to the amount of morphine u sed on the third postoperative day, Over-all, eleven of fourteen patie nts who completed questionnaires reported a decrease in pain between t he three and six-month evaluations, We concluded that continuous perin eural infusion of an anesthetic appears to be a safe, effective method for the relief of postoperative pain but that it does not prevent res idual or phantom-limb pain in patients who have had an amputation of t he lower extremity because of ischemic changes secondary to peripheral vascular disease.